Population normative data for three cognitive screening tools for older adults in sub-Saharan Africa.

In sub-Saharan Africa (SSA),cognitive screening is complicated by both cultural and educational factors, and the existing normative values may not be applicable. The Identification of Dementia in Elderly Africans (IDEA) cognitive screen is a low-literacy measure with good diagnostic accuracy for dementia. OBJECTIVE: The aim of this study is to report normative values for IDEA and other simple measures [i.e., categorical verbal fluency, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) 10-word list] in representative community-dwelling older adults in SSA. METHODS: Individuals aged ≥60 years resident in 12 representative villages in Kilimanjaro, Tanzania and individuals aged ≥65 years resident within three communities in Akinyele Local Government Area, Oyo State, Nigeria underwent cognitive screening. The normative data were generated by the categories of age, sex, and education. RESULTS: A total of 3,011 people in Tanzania (i.e., 57.3% females and 26.4% uneducated) and 1,117 in Nigeria (i.e., 60.3% females and 64.5% uneducated) were screened. Individuals with higher age, lower education, and female gender obtained lower scores. The 50th decile values for IDEA were 13 (60-64 years) vs. 8/9 (above 85 years), 10-11 uneducated vs. 13 primary educated, and 11/12 in females vs. 13 in males. The normative values for 10-word list delayed recall and categorical verbal fluency varied with education [i.e., delayed recall mean 2.8 [standard deviation (SD) 1.7] uneducated vs. 4.2 (SD 1.2) secondary educated; verbal fluency mean 9.2 (SD 4.8) uneducated vs. 12.2 (SD 4.3) secondary educated], substantially lower than published high-income country values. CONCLUSIONS: The cut-off values for commonly used cognitive screening items should be adjusted to suit local normative values, particularly where there are lower levels of education.

Na África Subsaariana (ASS), a triagem cognitiva é complicada por fatores culturais e educacionais, além dos valores normativos existentes poderem não ser aplicáveis. O rastreio cognitivo Identification of Dementia in Elderly Africans (IDEA) é uma medida para níveis baixos de alfabetização com boa acurácia diagnóstica para demência. OBJETIVO: Relatar os valores normativos para a IDEA e outras medidas simples (fluência verbal categórica, a lista de 10 palavras do Consortium to Establish a Registry for Alzheimer's Disease (CERAD) em idosos residentes na comunidade, representativos da ASS. Métodos: Indivíduos com idade ≥60 residentes em 12 comunidades representativas em Kilimanjaro, Tanzânia e indivíduos com idade ≥65 anos residentes em três comunidades na área governamental de Akinyele, Estado de Oyo, Nigéria, foram submetidos à triagem cognitiva. Os dados normativos foram gerados por faixas etárias, sexo e escolaridade. RESULTADOS: Um total de 3.011 pessoas na Tanzânia (57,3% mulheres, 26,4% sem educação) e 1.117 na Nigéria (60,3% mulheres, 64,5% sem educação) foram examinadas. Os indivíduos com idade mais alta, menor escolaridade e mulheres obtiveram escores mais baixos. Os valores do percentil 50 para a IDEA foram 13 (60­64 anos) vs. 8/9 (85+ anos), 10­11 para analfabetos vs. 13 com educação primária e 11/12 em mulheres vs. 13 em homens. Os valores normativos para a evocação tardia da lista de 10 palavras e a fluência verbal categórica variaram com a educação (evocação tardia 2,8 (SD 1,7) para os sem educação, vs. 4,2 (SD 1,2) para com educação secundária; fluência verbal 9,2 (DP 4,8) para os sem educação vs. 12,2 (SD 4.3) para os com ensino médio, substancialmente inferior aos valores publicados em países de alta renda. CONCLUSÕES: Os valores de corte para testes de triagem cognitiva comumente usados devem ser ajustados para se adequar aos valores normativos locais, particularmente em níveis baixos de educação.

Population normative data for three cognitive screening tools for older adults in sub-Saharan Africa / Dados normativos populacionais para três instrumentos de triagem cognitiva para idosos na áfrica subsaariana

ABSTRACT In sub-Saharan Africa (SSA),cognitive screening is complicated by both cultural and educational factors, and the existing normative values may not be applicable. The Identification of Dementia in Elderly Africans (IDEA) cognitive screen is a low-literacy measure with good diagnostic accuracy for dementia. Objective: The aim of this study is to report normative values for IDEA and other simple measures [i.e., categorical verbal fluency, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) 10-word list] in representative community-dwelling older adults in SSA. Methods: Individuals aged ≥60 years resident in 12 representative villages in Kilimanjaro, Tanzania and individuals aged ≥65 years resident within three communities in Akinyele Local Government Area, Oyo State, Nigeria underwent cognitive screening. The normative data were generated by the categories of age, sex, and education. Results: A total of 3,011 people in Tanzania (i.e., 57.3% females and 26.4% uneducated) and 1,117 in Nigeria (i.e., 60.3% females and 64.5% uneducated) were screened. Individuals with higher age, lower education, and female gender obtained lower scores. The 50th decile values for IDEA were 13 (60-64 years) vs. 8/9 (above 85 years), 10-11 uneducated vs. 13 primary educated, and 11/12 in females vs. 13 in males. The normative values for 10-word list delayed recall and categorical verbal fluency varied with education [i.e., delayed recall mean 2.8 [standard deviation (SD) 1.7] uneducated vs. 4.2 (SD 1.2) secondary educated; verbal fluency mean 9.2 (SD 4.8) uneducated vs. 12.2 (SD 4.3) secondary educated], substantially lower than published high-income country values. Conclusions: The cut-off values for commonly used cognitive screening items should be adjusted to suit local normative values, particularly where there are lower levels of education.

RESUMO Na África Subsaariana (ASS), a triagem cognitiva é complicada por fatores culturais e educacionais, além dos valores normativos existentes poderem não ser aplicáveis. O rastreio cognitivo Identification of Dementia in Elderly Africans (IDEA) é uma medida para níveis baixos de alfabetização com boa acurácia diagnóstica para demência. Objetivo: Relatar os valores normativos para a IDEA e outras medidas simples (fluência verbal categórica, a lista de 10 palavras do Consortium to Establish a Registry for Alzheimer's Disease (CERAD) em idosos residentes na comunidade, representativos da ASS. Métodos: Indivíduos com idade ≥60 residentes em 12 comunidades representativas em Kilimanjaro, Tanzânia e indivíduos com idade ≥65 anos residentes em três comunidades na área governamental de Akinyele, Estado de Oyo, Nigéria, foram submetidos à triagem cognitiva. Os dados normativos foram gerados por faixas etárias, sexo e escolaridade. Resultados: Um total de 3.011 pessoas na Tanzânia (57,3% mulheres, 26,4% sem educação) e 1.117 na Nigéria (60,3% mulheres, 64,5% sem educação) foram examinadas. Os indivíduos com idade mais alta, menor escolaridade e mulheres obtiveram escores mais baixos. Os valores do percentil 50 para a IDEA foram 13 (60-64 anos) vs. 8/9 (85+ anos), 10-11 para analfabetos vs. 13 com educação primária e 11/12 em mulheres vs. 13 em homens. Os valores normativos para a evocação tardia da lista de 10 palavras e a fluência verbal categórica variaram com a educação (evocação tardia 2,8 (SD 1,7) para os sem educação, vs. 4,2 (SD 1,2) para com educação secundária; fluência verbal 9,2 (DP 4,8) para os sem educação vs. 12,2 (SD 4.3) para os com ensino médio, substancialmente inferior aos valores publicados em países de alta renda. Conclusões: Os valores de corte para testes de triagem cognitiva comumente usados devem ser ajustados para se adequar aos valores normativos locais, particularmente em níveis baixos de educação.

Prevalence estimates of dementia in older adults in rural Kilimanjaro 2009-2010 and 2018-2019: is there evidence of changing prevalence?

INTRODUCTION: Although limited, existing epidemiological data on dementia in sub-Saharan Africa indicate that prevalence may be increasing; contrasting with recent decreases observed in high-income countries. We have previously reported the age-adjusted prevalence of dementia in rural Tanzania in 2009-2010 as 6.4% (95% confidence interval [CI] 4.9-7.9) in individuals aged ≥70 years. We aimed to repeat a community-based dementia prevalence study in the same setting to assess whether prevalence has changed. METHODS: This was a two-phase door-to-door community-based cross-sectional survey in Kilimanjaro, Tanzania. In Phase I, trained primary health workers screened all consenting individuals aged ≥60 years from 12 villages using previously validated, locally developed, tools (IDEA cognitive screen and IDEA-Instrumental Activities of Daily Living questionnaire). Screening was conducted using a mobile digital application (app) on a hand-held tablet. In Phase II, a stratified sample of those identified in Phase I were clinically assessed using the DSM-5 criteria and diagnoses subsequently confirmed by consensus panel. RESULTS: Of 3011 people who consented, 424 screened positive for probable dementia and 227 for possible dementia. During clinical assessment in Phase II, 105 individuals met DSM-5 dementia criteria. The age-adjusted prevalence of dementia was 4.6% (95% CI 2.9-6.4) in those aged ≥60 years and 8.9% (95% CI 6.1-11.8) in those aged ≥70 years. Prevalence rates increased significantly with age. CONCLUSIONS: The prevalence of dementia in this rural Tanzanian population appears to have increased since 2010, although not significantly. Dementia is likely to become a significant health burden in this population as demographic transition continues.

Effectiveness of App-Based Cognitive Screening for Dementia by Lay Health Workers in Low Resource Settings. A Validation and Feasibility Study in Rural Tanzania.

BACKGROUND: The majority of people with dementia live in low-and middle-income countries (LMICs). In sub-Saharan Africa (SSA) human-resource shortages in mental health and geriatric medicine are well recognized. Use of technological solutions may improve access to diagnosis. We aimed to assess the diagnostic accuracy of a brief dementia screening mobile application (app) for non-specialist workers in rural Tanzania against blinded gold-standard diagnosis of DSM-5 dementia. The app includes 2 previously-validated culturally appropriate low-literacy screening tools for cognitive (IDEA cognitive screen) and functional impairment (abbreviated IDEA-IADL questionnaire). METHODS: This was a 2-stage community-based door-to-door study. In Stage1, rural primary health workers approached all individuals aged ≥60 years for app-based dementia screening in 12 villages in Hai district, Kilimanjaro Tanzania.In Stage 2, a stratified sub-sample were clinically-assessed for dementia blind to app screening score. Assessment included clinical history, neurological and bedside cognitive assessment and collateral history. RESULTS: 3011 (of 3122 eligible) older people consented to screening. Of these, 610 were evaluated in Stage 2. For the IDEA cognitive screen, the area under the receiver operating characteristic (AUROC) curve was 0.79 (95% CI 0.74-0.83) for DSM-5 dementia diagnosis (sensitivity 84.8%, specificity 58.4%). For those 358 (44%) completing the full app, AUROC was 0.78 for combined cognitive and informant-reported functional assessment. CONCLUSIONS: The pilot dementia screening app had good sensitivity but lacked specificity for dementia when administered by non-specialist rural community workers. This technological approach may be a promising way forward in low-resource settings, specialist onward referral may be prioritized.

Monitoring Walking Activity with Wearable Technology in Rural-dwelling Older Adults in Tanzania: A Feasibility Study Nested within a Frailty Prevalence Study.

BACKGROUND: Older adults with lower levels of activity can be at risk of poor health outcomes. Wearable technology has improved the acceptability and objectivity of measuring activity for older adults in high-income countries. Nevertheless, the technology is under-utilized in low-to-middle income countries. The aim was to explore feasibility, acceptability and utility of wearable technology to measure walking activity in rural-dwelling, older Tanzanians. METHODS: A total of 65 participants (73.9 ± 11.2 years), 36 non-frail and 29 frail, were assessed. Free-living data were recorded for 7 days with an accelerometer on the lower back. Data were analyzed via an automatic cloud-based pipeline: volume, pattern and variability of walking were extracted. Acceptability questionnaires were completed. T-tests were used for comparison between the groups. RESULTS: 59/65 datasets were analyzed. Questionnaires indicated that 15/65 (23.0%) experienced some therapeutic benefit from the accelerometer, 15/65 (23.0%) expected diagnostic benefit; 16/65 (24.6%) experienced symptoms while wearing the accelerometer (e.g. itching). Frail adults walked significantly less, had less variable walking patterns, and had a greater proportion of shorter walking bouts compared to the non-frail. CONCLUSION: This study suggests that important contextual and practical limitations withstanding wearable technology may be feasible for measuring walking activity in older rural-dwelling adults in low-income settings, identifying those with frailty.

The prevalence and characteristics of frailty by frailty phenotype in rural Tanzania.

BACKGROUND: The frailty phenotype is defined by the presence of three from the following five clinical features: weakness, slow walking speed, unintentional weight loss, exhaustion, and low physical activity. It has been widely applied in different research and clinical contexts, including across many low and middle-income countries. However, there is evidence that the operationalisation of each component of the frailty phenotype significantly alters its characteristics and predictive validity, and care is needed when applying the phenotype across settings. The study's objective was to operationalise the frailty phenotype in a rural Tanzanian population of older community-dwelling adults. METHODS: Consenting adults aged ≥60 years, and resident in five randomly selected villages of Hai district Demographic Surveillance Site, were eligible to participate in this cross-sectional study. From a screened sample of 1207 older adults, 235 were randomised and consented to an assessment of their frailty status by the frailty phenotype. Trained research fieldworkers (Tanzanian medical doctors and nurses) carried out measurements and questionnaires at local village centres or at participants' homes. RESULTS: The prevalence of the frailty phenotype, calculated from complete data for 196 participants, was 9.25% (95% CI 4.39-14.12) When missing data were counted as meeting frailty criterion (i.e. missing due to inability to perform an assessment), the prevalence increased to 11.22% (95% CI 7.11-15.32). Frailty by phenotype criteria was more common in older age groups, and was associated with self-assessed poor health and depression symptoms. CONCLUSIONS: Frailty can be successfully estimated using the frailty phenotype, however there are challenges in its operationalisation cross-culturally. Further work is needed to explore the potential clinical application of the frailty phenotype in such settings.

Screening for Instrumental Activities of Daily Living in Sub-Saharan Africa: A Balance Between Task Shifting, Simplicity, Brevity, and Training.

BACKGROUND: Task shifting has been suggested as one way to help manage the increasing burden of dementia in sub-Saharan Africa (SSA). However, brief, easy-to-use and valid screening tools are needed to support this approach. Our team has developed an 11-item questionnaire to assess instrumental activities of daily living (IADLs) in SSA, the Identification and Intervention for Dementia in Elderly Africans (IDEA)-IADL questionnaire. We aimed to externally validate the questionnaire and develop a shorter, more efficient version. METHODS: A community-based sample of 329 older adults in 4 rural villages was screened for dementia using the validated IDEA cognitive screen and the 11-item IDEA-IADL questionnaire. A stratified sample was assessed for Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) dementia by a United Kingdom-based doctor, who was blinded to the results of screening. Area under the receiver operating characteristic (AUROC) curve analysis was used to assess validity, and factor analysis and regression modeling were used to develop a shorter version of the questionnaire. RESULTS: A 3-item IDEA-IADL questionnaire was developed and externally validated in the study sample. The questionnaire was deemed to be valid and enhanced screening performance in 2 villages (AUROC: 0.857 and 0.895) but detracted from the accuracy of the IDEA cognitive screen in the other 2 villages (AUROC: 0.591 and 0.639). These differences appeared to be due to differences in interpretation of responses to questions by the assessors. CONCLUSIONS: A brief IDEA-IADLs scale was developed and worked well in some villages. However, our study highlights a training need if brief screening tools to assess IADLs are to be effectively used by nonspecialists in low-resource settings.

Prevalence of Frailty in Older Community-Dwelling Tanzanians According to Comprehensive Geriatric Assessment.

OBJECTIVES: To investigate the prevalence of frailty using a Comprehensive Geriatric Assessment (CGA) in older community-dwelling adults living in rural northern Tanzania. DESIGN: Cross-sectional survey. SETTING: Five randomly selected villages in Hai District, Kilimanjaro region, Tanzania. PARTICIPANTS: All adults aged 60 and older living in the selected villages were eligible to participate, including older adults with cognitive impairment provided a close relative was able to assent on their behalf. All participants were community dwelling because institutionalization is very rare. MEASUREMENTS: Participants were screened using a short frailty screening tool, the Brief Frailty Instrument for Tanzania (B-FIT), comprising an abbreviated test of cognitive function and the Barthel Index, which assesses functional independence. Based on B-FIT score, a frailty-weighted, stratified sample was selected for in-depth assessment using CGA and characterized as frail or not frail. RESULTS: Two hundred thirty-six CGAs were performed in 1,207 people screened, 91 of whom were deemed frail. After adjusting for stratification, the prevalence of frailty was 19.1% (95% confidence interval=15.2-23.1). CONCLUSION: This is the first study in sub-Saharan Africa to report the prevalence of frailty in community-dwelling older adults according to a CGA. The strengths of reporting frailty according to a CGA include the ability to consider likely medical diagnoses based on clinical assessment and to assess individuals' social circumstances and environment.

A longitudinal study of cognitive decline in rural Tanzania: rates and potentially modifiable risk factors.

ABSTRACTBackground:The number of people living with dementia in sub-Saharan Africa (SSA) is expected to increase rapidly in the coming decades. However, our understanding of how best to reduce dementia risk in the population is very limited. As a first step in developing intervention strategies to manage dementia risk in this setting, we investigated rates of cognitive decline in a rural population in Tanzania and attempted to identify associated factors. METHODS: The study was conducted in the rural Hai district of northern Tanzania. In 2014, community-dwelling people aged 65 years and over living in six villages were invited to take part in a cognitive screening program. All participants from four of the six villages were followed-up at two years and cognitive function re-tested. At baseline and follow-up, participants were assessed for functional disability, hypertension, and grip strength (as a measure of frailty). At follow-up, additional assessments of visual acuity, hearing impairment, tobacco and alcohol consumption, and clinical assessment for stroke were completed. RESULTS: Baseline and follow-up data were available for 327 people. Fifty people had significant cognitive decline at two-year follow-up. Having no formal education, low grip strength at baseline, being female and having depression at follow-up were independently associated with cognitive decline. CONCLUSIONS: This is one of the first studies of cognitive decline conducted in SSA. Rates of decline at two years were relatively high. Future work should focus on identification of specific modifiable risk factors for cognitive decline with a view to developing culturally appropriate interventions.

Cognitive stimulation therapy as a sustainable intervention for dementia in sub-Saharan Africa: Feasibility and clinical efficacy using a stepped-wedge design - ERRATUM.

In the above article (Paddick, 2017) The corresponding author's details were previously listed incorrectly. The correct details are; contact number +44 191 293 2709 and email address William.gray@nhct.nhs.uk. The original article has been updated with the correct contact details. The publishers apologise for any inconvenience and confusion this error has caused.

The role of traditional and faith healers in the treatment of dementia in Tanzania and the potential for collaboration with allopathic healthcare services.

Background: Low diagnostic rates are a barrier to improving care for the growing number of people with dementia in sub-Saharan Africa. Many people with dementia are thought to visit traditional healers (THs) and Christian faith healers (FHs) and these groups may have a role in identifying people with dementia. We aimed to explore the practice and attitudes of these healers regarding dementia in rural Tanzania and investigate attitudes of their patients and their patients' carers. Methods: This was a qualitative study conducted in Hai district, Tanzania. Semi-structured interviews were conducted with a convenience sample of THs and FHs and a purposive-stratified sample of people with dementia and their carers. Interview guides were devised which included case vignettes. Transcripts of interviews were subject to thematic analysis. Findings: Eleven THs, 10 FHs, 18 people with dementia and 17 carers were recruited. Three themes emerged: (i) conceptualisation of dementia by healers as a normal part of the ageing process and no recognition of dementia as a specific condition; (ii) people with dementia and carer reasons for seeking help and experiences of treatment and the role of prayers, plants and witchcraft in diagnosis and treatment; (iii) willingness to collaborate with allopathic healthcare services. FHs and people with dementia expressed concerns about any collaboration with THs. Conclusions: Although THs and FHs do not appear to view dementia as a specific disease, they may provide a means of identifying people with dementia in this setting.

Cognitive stimulation therapy as a sustainable intervention for dementia in sub-Saharan Africa: feasibility and clinical efficacy using a stepped-wedge design.

BACKGROUND: Cognitive stimulation therapy (CST) is a psychosocial group-based intervention for dementia shown to improve cognition and quality of life with a similar efficacy to cholinesterase inhibitors. Since CST can be delivered by non-specialist healthcare workers, it has potential for use in low-resource environments, such as sub-Saharan Africa (SSA). We aimed to assess the feasibility and clinical effectiveness of CST in rural Tanzania using a stepped-wedge design. METHODS: Participants and their carers were recruited through a community dementia screening program. Inclusion criteria were DSM-IV diagnosis of dementia of mild/moderate severity following detailed assessment. No participant had a previous diagnosis of dementia and none were taking a cholinesterase inhibitor. Primary outcomes related to the feasibility of conducting CST in this setting. Key clinical outcomes were changes in quality of life and cognition. The assessing team was blind to treatment group membership. RESULTS: Thirty four participants with mild/moderate dementia were allocated to four CST groups. Attendance rates were high (85%) and we were able to complete all 14 sessions for each group within the seven week timeframe. Substantial improvements in cognition, anxiety, and behavioral symptoms were noted following CST, with smaller improvements in quality of life measures. The number needed to treat was two for a four-point cognitive (adapted Alzheimer's Disease Assessment Scale-Cognitive) improvement. CONCLUSIONS: This intervention has the potential to be low-cost, sustainable, and adaptable to other settings across SSA, particularly if it can be delivered by non-specialist health workers.

Community validation of the IDEA study cognitive screen in rural Tanzania.

OBJECTIVES: The dementia diagnosis gap in sub-Saharan Africa (SSA) is large, partly because of difficulties in screening for cognitive impairment in the community. As part of the Identification and Intervention for Dementia in Elderly Africans (IDEA) study, we aimed to validate the IDEA cognitive screen in a community-based sample in rural Tanzania METHODS: Study participants were recruited from people who attended screening days held in villages within the rural Hai district of Tanzania. Criterion validity was assessed against the gold standard clinical dementia diagnosis using DSM-IV criteria. Construct validity was assessed against, age, education, sex and grip strength and instrumental activities of daily living (IADLs). Internal consistency and floor and ceiling effects were also examined. RESULTS: During community screening, the IDEA cognitive screen had high criterion validity, with an area under the receiver operating characteristic curve of 0.855 (95% CI 0.794 to 0.915). Higher scores on the screen were significantly correlated with lower age, male sex, having attended school, better grip strength and improved performance in activities of daily living. Factor analysis revealed a single factor with an eigenvalue greater than one, although internal consistency was only moderate (Cronbach's alpha = 0.534). CONCLUSIONS: The IDEA cognitive screen had high criterion and construct validity and is suitable for use as a cognitive screening instrument in a community setting in SSA. Only moderate internal consistency may partly reflect the multi-domain nature of dementia as diagnosed clinically. Copyright © 2016 John Wiley & Sons, Ltd.

Rates and predictors of three-year mortality in older people in rural Tanzania.

BACKGROUND: There are few data on mortality rates in the general elderly living in sub-Saharan Africa. We aimed to detail three-year mortality rates in a population of rural community-dwelling older adults in northern Tanzania. METHODS: We performed a community-based study of 2232 people aged 70 years and over living in Hai district, Tanzania. At baseline, participants underwent clinical assessment for disability, neurological disorders, hypertension, atrial fibrillation and memory problems. At three-year follow-up mortality data were collected. Mortality rates were compared to UK estimates. RESULTS: At follow-up, data were available for 1873 subjects (83.9%). Of those, 208 (11.1%, 95% CI 9.7-12.5) had died. The age-standardised mortality rate was 10.2% (95% CI 8.8-11.6). Age-standardised mortality rates were lower than estimated for the UK (13.9%). In Cox regression analysis, greater age, higher levels of functional disability, use of a walking aid, subjective report of memory problems, being severely underweight and being normotensive were significant predictors of mortality. CONCLUSIONS: Those who survive to old age in Tanzania appear to have relatively low mortality rates. Physical and cognitive disabilities were strongly associated with mortality risk in this elderly community-dwelling population. The association between blood pressure and mortality merits further study.

Validation of the Identification and Intervention for Dementia in Elderly Africans (IDEA) cognitive screen in Nigeria and Tanzania.

BACKGROUND: We have previously described the development of the Identification and Intervention for Dementia in Elderly Africans (IDEA) cognitive screen for use in populations with low levels of formal education. The IDEA cognitive screen was developed and field-tested in an elderly, community-based population in rural Tanzania with a relatively high prevalence of cognitive impairment. The aim of this study was to validate the IDEA cognitive screen as an assessment of major cognitive impairment in hospital settings in Nigeria and Tanzania. METHODS: In Nigeria, 121 consecutive elderly medical clinic outpatients reviewed at the University College Hospital, Ibadan were screened using the IDEA cognitive screen. In Tanzania, 97 consecutive inpatients admitted to Mawenzi Regional Hospital (MRH), Moshi, and 108 consecutive medical clinic outpatients attending the geriatric medicine clinic at MRH were screened. Inter-rater reliability was assessed in Tanzanian outpatients attending St Joseph's Hospital in Moshi using three raters. A diagnosis of dementia or delirium (DSM-IV criteria) was classified as major cognitive impairment and was provided independently by a physician blinded to the results of the screening assessment. RESULTS: The area under the receiver operating characteristic (AUROC) curve in Nigerian outpatients, Tanzanian outpatients and Tanzanian inpatients was 0.990, 0.919 and 0.917 respectively. Inter-rater reliability was good (intra-class correlation coefficient 0.742 to 0.791). In regression models, the cognitive screen did not appear to be educationally biased. CONCLUSIONS: The IDEA cognitive screen performed well in these populations and should prove useful in screening for dementia and delirium in other areas of sub-Saharan Africa.

The prevalence of Parkinson's disease in rural Tanzania.

The prevalence of Parkinson's disease (PD) varies worldwide from 7 to 450 per 100,000, and appears low in sub-Saharan Africa (SSA) but few data exist. We conducted a prevalence study of PD in rural Tanzania. A door-to-door study was conducted in the Hai district project area (population 161,071), using a screening questionnaire followed by structured history and examination of positive responders. Diagnosis was based on the UK PD Society Brain Bank Criteria. 33 (23 men) cases of PD were detected, with mean age 74 years (range 38-94). One patient died before the prevalence date. 78% were previously undiagnosed and untreated. Mean duration of symptoms was 5 years, and median Hoehn and Yahr stage 3. Crude prevalence rates were 30/100,000 (men), 11/100,000 (women) and 20/100,000 (combined). The direct age-standardized prevalence rates compared with the UK population were 64/100,000 (men), 20/100,000 (women) and 40/100,000 (combined). These rates are higher than previously reported from SSA, but still lower than the developed world. Many PD patients in SSA may never be diagnosed or treated, with consequent reduction in their life expectancy and quality of life. With the world population ageing PD is predicted to become an increasing problem.